18329840 has 20 divisors (see below), whose sum is σ = 42617064. Its totient is φ = 7331904.

The previous prime is 18329833. The next prime is 18329863. The reversal of 18329840 is 4892381.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 18329840.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114482 + ... + 114641.

Almost surely, 2^18329840 is an apocalyptic number.

18329840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18329840 is an abundant number, since it is smaller than the sum of its proper divisors (24287224).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18329840 is a wasteful number, since it uses less digits than its factorization.

18329840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229136 (or 229130 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 18329840 is about 4281.3362400073. The cubic root of 18329840 is about 263.6652475830.

The spelling of 18329840 in words is "eighteen million, three hundred twenty-nine thousand, eight hundred forty".